Since you have to replace it.... you might think about TPO instead.
The sun doesn't hurt TPO, it is tough... almost impossible to punch a hole in without a firearm.
It will not oxidize (chalk)
No streaks on the sides of your camper from the milky edpm oxide run-off.
It comes in a roll 8' wide and as long as you need. Roll the edges over the roof's slightly... rain runs off. You can cut it with industrial sissors or a good utility knife... for the AC, and other vents.
I originally had an aluminum roof... I have had a TPO roof since 2006. Lance installed it (insurance job)
Good luck
Sleepy